1. Technical Field
The present invention is directed toward window hinges, and more particularly toward a unique design for a hat design for ensuring proper alignment of the hinge sash arm and links with the hinge track when closed.
2. Background Art
Window hinges are known in the art for providing pivotal movement of a window between a closed position (with the window sash sealed against the window frame) and an open positions (with the window sash usually projecting out of the room in which the window is located). Window hinges typically involve an elongated track mountable to a window frame, a sash arm mountable along to a window sash, and a plurality of links pivotally interconnecting the sash bar with the track so that the sash bar is movable in a plane. Typically it is desirable for the track, sash arm, and links to all be aligned when the window sash is closed, as misaligned components can result in long term bending stresses on pivots which in turn can result in bending and undesirable binding during operation of the hinge.
To achieve alignment of the links and sash arm with the track, some window hardware manufacturers mold a separate component of zinc or plastic to go into the track or the sash bar that are designed specifically for left- or right-handed hinges. Since both types of hinges are required, the requirement of separate, distinctive parts of such different operating hinges can create additional costs for manufacturing and storage. Individual tools or molds may be required to produce each the separate components, thereby increasing the cost of those components. Further, undesirable (and costly) delays can result where the wrong hinges (i.e., left-handed hinges where right-handed hinges are required, and vice versa) are supplied to a site during installation.
U.S. Pat. No. 4,674,149 shows a particular hat design which has been used to ensure alignment of the hinge components when the sash is closed. This design includes a V-shaped hat secured to the end of the track and interacting with a V-shaped cam surface on the end of the sash bar during closing of the window to align the sash bar and links with the track. Such a hat configuration can operate adequately, although manufacture and operational problems can arise. Specifically, the V-shaped hat can be relatively expensive to make from metal components. Further, while such hats can be relatively inexpensively made of hard plastic, those hats are less able to withstand high stresses which can occur occasionally with any window installation, particularly in view of the high stress concentrations occurring at narrow engagement of the hat with the end of the sash bar. Still further, while the V-shaped hat design can be used in both right-handed and left-handed hinges, it unavoidably provides less strength when installed, inasmuch as in any given installation only one side of the "V" functions to guide and maintain the sash bar in alignment with the links.
The present invention is directed toward overcoming one or more of the problems set forth above.